Redmine

First:

What's the "API key " usage? (Administrator-->Settings-->Receive email)

Second:

Jean-Philippe Lang wrote in Feature #3569, said:

Replying a ticket via email is implemented.

But I don't know how to configure redmine to make it can do this.

So, please tell me how.

Thanks

My system is:

Ubuntu 8.04 + mongrel + apache2 + redmine_2845 at computer A.
Using Lotus Notes as email server at computer B.
Working at computer C (Windows XP)

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Jiongliang